We have demonstrated the benefit of symmetric matrix solver (SMS), partial matrix solver (PMS) and iterative matrix solver(IMS) for filter design in example 20. We will demonstrate the application of SMS and IMS for antenna array simulation. We will use the coupled-fed circular patch antenna in example 8 as our example. An 8-element array with spacing of 50 mm is shown in Figure 21.1. A speed comparison is shown in Table 21.1. We observed speed improvement over 500% on the IMS over the SMS. The magnitudes of the s-parameters of the 8-element array is shown in Figure 21.2. The maximum element-to-element coupling is about -15 dB.The radiation pattern of the 8-element array with uniform excitation, considering the coupling between elements, is shown in Figure 21.3. On the IE3D, you can calculate the array radiation pattern based upon the simulation on one single element. In such a case, we neglect the coupling effect between elements. Surprisingly, the array radiation pattern based upon single element radiation pattern and the array factor is almost identical to the one shown in Figure 21.3. What it means is that the element-to-element coupling does not have significant effect to the radiation pattern for this particular structure.

Figure 21.1 An 8-element coupled fed circular patch array.

Table 20.1 Speed comparison between the SMS and IMS for arrays with different number of elements (Pentium 133)

Figure 21.2 An 8-element coupled fed circular patch array.

Figure 21.3 The radiation pattern of the 8-elementarray.